Cations impact the biodegradation of iodosulfuron-methyl herbicidal ionic liquids by fungi

ABSTRACT

In the framework of this study, six fungal isolates which demonstrated a high capability for biodegrading iodosulphuron-methyl sodium as well as herbicidal ionic liquids based on this herbicide were isolated from different soil samples. The isolates were identified based on the ITS region, whereas biodegradation residues were determined based on LC-MS/MS. Depending on the isolate, the half-lives values of the biodegraded herbicide or herbicidal ionic liquid ranged significantly from just 1.25 days to more than 40 days. The research findings unveiled that the structure of cations is a central limiting factor affecting fungal growth and herbicide transformation in case of ionic liquids. The length of the alkyl chain has been identified as the primary driver of herbicide toxicity, emphasizing the importance of structural factors in herbicide design. In cases when dodecyl(2-hydroxyethyl)dimethyl cation was used, its biodegradation ranged from 0 to approx. 20% and the biodegradability of the iodosulfuron-methyl was notably limited for the majority of the studied isolates. This knowledge provides guidance for development and selection of herbicides with reduced environmental impact. This study highlights the ecological importance of soil fungi, their potential role in herbicide biodegradation, the influence of cations on fungal growth and herbicide transformation, and the structural factors governing herbicide toxicity. Further research in these areas may lead to more efficient and environmentally friendly approaches to herbicide management.

GRAPHICAL ABSTRACT

KEYWORDS:

• Biodegradation
• herbicides
• herbicidal ionic liquids
• iodosulphuron-methyl sodium
• fungi

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Data availability statement

All data supporting the findings of this study are available within the paper and Supplementary Information (NMR spectra and average values of residues after biodegradation). Should any raw data files be needed in another format, they are available from the corresponding author upon reasonable request.

Author contribution statement

JH designed the research, carried out the experiments, analysed the data and wrote the manuscript; KK conducted the experiments; WS and MN contributed chemical reagents and carried out the synthesis; RF and AZG provided analytical tools and conducted the residue analysis; LL revised the manuscript; LC supervised the experiment and provided funding.

Additional information

Funding

This study was conducted in the framework of OPUS 15 entirely funded by the National Science Centre in Poland, conferred on the basis of decision DEC-2018/29/B/NZ9/01136. Grant title ‘Bioaugmentation with herbicide degrading bacteria as a potential factor in spreading resistance to herbicides among plants’ as well as project SONATA 14 funded by the National Science Centre in Poland, conferred on the basis of decision DEC-2018/31/D/ST5/01057.